VISUALIZATION OF ROD PHOTORECEPTORS WITH GFP IN TRANSGENIC ZEBRAFISH

"The vertebrate retina is an accessible part of the brain that consists of 7 major cell types arranged in multiple layers. A number of molecular pathways and signaling molecules are required to generate this cellular diversity. To facilitate the understanding of these processes, forward genetic screens in zebrafish have been perfor med to identify mutations that disrupt neurogenesis of the retina. Zebrafish that express a rod photoreceptor specific GFP transgene have been integrated into this screen in order to directly identify mutants that affect the rods. This image shows a ventral view of a living transgenic zebrafish at 4 days of age with the rod photoreceptors expressing the GFP transgene (cells in green). As the animal continues to grow, this patch of cells will eventually expand and fill both the ventral and dorsal retina. Mutations affecting this process can be studied and the genes identified to understand how cells within the nervous system develop."